1. Field of the Invention
The present invention relates to a 3D imaging apparatus. More particularly, the present invention relates to a 2D/3D switchable imaging apparatus.
2. Description of the Related Art
In recent years, 3D imaging apparatus technologies may be mainly classified into two categories: glasses 3D imaging, and naked-eye 3D imaging technologies. The glasses 3D imaging technology utilizes glasses to polarize light so as to make the user's left eye and right eye see the image corresponding to the left eye and the image corresponding to the right eye, respectively. The naked-eye 3D imaging technology utilizes a light modulator directly disposed on the display device to control or change the refraction angle of light so as to make the user's left eye and right eye see the image corresponding to the left eye and the image corresponding to the right eye, respectively. The light modulator is usually a barrier layer or a lenticular structure, such as a lenticular lens. Since the naked-eye 3D imaging technology needs no glasses, it is a relatively easier way to show the 3D image.
In many applications, the 3D imaging apparatus is required to be able to switch between a 2D imaging mode and a 3D imaging mode. For example, the user is more likely to experience fatigue after viewing the 3D imaging mode for awhile, and switching to the 2D imaging mode can make the user feel more relaxed. Alternatively, the 2D imaging mode is better than the imaging 3D mode when better resolution is needed. Thus, a 2D/3D switchable imaging apparatus is developed, in particular, switched using an electric field.
A lenticular lens structural 3D imaging apparatus is one of various kinds of 3D imaging apparatuses. The lenticular lens structural 3D imaging apparatus comprises a lens structural layer interposed between two electrode layers. Each of the lenticular lens structure comprises liquid-crystal monomers filled therein. The liquid-crystal monomers are arranged along a direction not refracting light when no electric field is applied, so that each eye of the user can see the images of all the pixels. In addition, the liquid-crystal monomers will be arranged to a direction refracting the light when an electric field is applied, so that the user's left eye and right eye, respectively, can only see the image of the left-eye pixels and the image of right-eye pixels. Thus the 3D image is shown.
For the lenticular lens structural 3D imaging apparatus, although the 2D/3D modes can be switched by a variation of the applied electric field, increases in sizes and resolution are associated with increasing numbers of the lens structure and a larger cell gap of the lens structural layer. As such, more power consumption will be incurred since a higher electric filed is needed to drive the liquid-crystal monomers, and the rate of liquid-crystal monomers in responding to the electric field may get slower, even slow enough to be observed by the user. In addition, in the 2D image mode, the liquid-crystal monomers in the lens structural layer are easily dispersed by forcing, which is called to push mura problems, resulting in instability of the lenticular lens structural 3D imaging apparatus.
Therefore, a 2D/3D switchable imaging apparatus capable of addressing the above issues is needed.